The Mobile Desktop Dock
The Mobile Desktop Dock gives ROG Phone II unprecedented expansion capabilities. Connect to an external 4K UHD monitor, mouse and keyboard while using ROG Phone II as an auxiliary display, hook up to a wired gigabit LAN and use the S/PDIF output to drive 5.1-channel surround-sound system.

 The dock allows users to connect to a 4K UHD 60Hz display via a HDMI or DisplayPort (please note that not all TVs support 60hz signal from all of its inputs), add USB-mouse, keyboard, RJ-45 LAN, 3.5mm audio jack, and S/PDIF audio out, to transform the ROG Phone II into a desktop gaming rig.

 The dock also allows users to switch instantly between ROG Phone II and  PC so users can continue using the same gaming gear without any interruption.

With the Key Mapping feature in Game Genie, users can replace touch screen actions with a keyboard and mouse, so that ROG Phone can be used in desktop gaming mode. 
I/O port:
HDMI 2.0 standard
Gigabit LAN RJ45
USB 3.1 Gen 1 (Type-A)
SD slot (normal size)
3.5mm combo (headphone and S/PDIF out)
3.5mm microphone
Type-C power (for charging)
USB Micro B 3.0 (PC input)
Display port 1.2 (PC input)
Display port 1.2 (output)